would be great if one could add an field on a per adress-basis, which holds
the desired mailadress for mailing to that person.

example:
one owns several mailadresses: a (the default one),b,c
with maillinglist x, one could need to write with adress b, as this is the
subscribed one. 

now one has to select the adress while writing, but it would be coul to
have it selected automagically.

yours
josef